Japan's Shinrin-yoku (Forest Bathing) as a Mental Health Intervention in an Era of Climate Change
The effects of climate change are becoming increasingly more apparent with intensifying extreme weather events, rising sea levels, and worsening air quality, which poses a significant threat to ecosystems and public health worldwide. Located in East Asia comprising of over 6,800 islands, Japan has c
Background
Shinrin-yoku (Forest Bathing) in Japan (Photo courtesy of Future with Forest Foundation)
The effects of climate change are becoming increasingly more apparent with intensifying extreme weather events, rising sea levels, and worsening air quality, which poses a significant threat to ecosystems and public health worldwide. Located in East Asia comprising of over 6,800 islands, Japan has climate that varies by latitude, but the country generally experiences four distinct seasons (winter, spring, summer, and autumn) [1]. The population of Japan is over 120 million, 29 percent of which is aged 65 and older [1].
Japan is highly exposed to various climate hazards such as tropical storms, heavy rainfall, and flooding; it is also experiencing more frequent and increasingly intensifying typhoons [2,3]. Although Japan’s capacity to adapt to climate hazards is considered high due to its economy and disaster preparedness, several climate-related natural disasters in the past have caused significant impacts, including power outages, forced evacuation of residents, damaged buildings and infrastructure, and physical and mental harm to the people [4,5,6].
Mental health problems are already a significant concern in Japan. Approximately five million people in the nation receive treatments for mental and behavioral disorders [7], but this could be underreported.
Climate change and mental health in Japan
In a study that examined climate anxiety in four of the top emitters of greenhouse gases in the world: China, India, Japan, and the United States, it found that climate anxiety was lowest among the Japanese and American participants [8]. Meanwhile, Dentsu Institute conducted an online survey in 2023 on 1,000 people in Japan aged 16 to 25 years old that showed 72.6 percent of the respondents were “worried” about climate change and 49.1 percent agreed with the statement, “The emotional toll caused by climate change is negatively affecting my daily life.” [9].
Additionally, according to a 2023 survey conducted by marketing research company Cross Marketing targeting 2,400 men and women aged 20 to 79 across Japan, 74 percent of respondents reported feeling anxious about climate change. Respondents raised concerns about the impact on the environment, with 44 percent expressing that “Japan will lose its four seasons” due to record-breaking hot days, followed by 30 percent concerned about “changes in the habitat of fish and shellfish in Japanese waters.” Overall, respondents felt more anxious about the effects of natural disasters that could someday happen to them than about the impact of climate change on the ecosystem [10]. Interventions are needed to address climate anxiety, and one potential intervention is a nature-based solution that has existed in Japan for decades.
About shinrin-yoku (forest bathing)
In Japan, there is a strong tradition of using nature as a part of therapy, in what is known in Japanese as “shinrin-yoku,” which translates to “forest bathing” in English. The concept was first introduced in 1982 by Tomohide Akiyama, then director-general of the Forestry Agency, under the Ministry of Agriculture, Forestry and Fisheries. Akiyama aimed to address the stresses associated with urban life and technology. Based on the idea that “the forest holds unique antimicrobial properties that help maintain a healthy body,” he believed that spending time in the forest can benefit one’s physical and mental health [11].
The practice of shinrin-yoku involves immersing oneself in nature and connecting with it through our five senses [12]. Japan’s reverence for nature has a long history originating from Shinto religious beliefs that all natural objects, such as mountains, rivers, and trees, are inhabited by deities. Japanese people believe that nature and humans are equal beings, so for them, the health-promoting effects and comfort of forest bathing is intuitive [13]. Many researchers worldwide began studying the physiological and psychological benefits of shinrin-yoku as an intervention to provide insights into scientific evidence on the beneficial effects of the natural environment on human health [14,15,16]. Other studies have tested the effectiveness of shinrin-yoku in reducing stress hormone levels and cortisol levels, which suggests that shinrin-yoku may have preventive effects on non-communicable diseases, including cancers [17,18].
Shinrin-yoku has been associated with increasing serotonin levels among those who practice it and has been shown to regulate mood and improve overall mental health [19,20,21,22]. One systematic review and meta-analysis examined twenty studies (eight non-randomized and twelve randomized controlled trials) involving 2,257 participants, investigating the effects of shinrin-yoku on mental health. The findings concluded that shinrin-yoku was deemed effective for mental health conditions (depression, anxiety, stress, and anger), particularly with a greater effect on anxiety [23]. This suggests that shinrin-yoku could be an effective treatment for climate anxiety and other emotional consequences of climate change; however, its potential benefit for climate anxiety or climate/disaster-affected individuals is yet to be directly studied.
Due to the growing body of research investigating the effects of shinrin-yoku and forest environments on human health, “Forest Medicine” was developed as a new interdisciplinary science that studies the effects of shinrin-yoku and natural environments on human health. [24]. Soon after, the concept of “Forest Therapy” was introduced, which is a research-based healing practice that involves the practice of shinrin-yoku to improve physical and mental health as well as disease prevention while enjoying and appreciating the forest environment.
In 2004, the Japanese Society of Forest Therapy was established and has since certified more than 60 forest therapy bases in Japan [25]. With Japan’s forests accounting for approximately 70 percent of the land area, it makes participation in shinrin-yoku relatively accessible, and along with the therapeutic benefits, it was quickly embraced by Japanese people. In a 2019 public opinion survey, when asked in your daily life, what kind of things would you like to do in the forest, 60.2 percent of respondents said, “walking in the forest to improve physical and mental health” [26].
Forest therapy is now spreading worldwide [27] and has even been tested in virtual environments, as more and more people in industrialized cities may not have convenient access to forests or areas with nature. A study that compared the physiological and psychological effects of digital shinrin-yoku with that of studies conducted in a real forest environment, found that the digital forest environment decreased negative psychological factors, such as “anxiety,” “depression,” “anger,” and increased the restorative traits, similar to the effects of an actual forest environment [28].
Key insights
Shinrin-yoku as an intervention has provided several important insights. First, forests and other natural environments are considered to be ‘therapeutic’ with various beneficial effects on human health, such as reducing depression and anxiety and even the occurrence of chronic diseases. People experiencing climate anxiety are likely to have strong connections to the natural environment, so shinrin-yoku may be one effective treatment to help with coping from its symptoms. Second, the activities practiced during shinrin-yoku typically include meditation, walking, or taking in the landscape. The low-intensity nature of these activities allows individuals from all populations to practice, regardless of physical limitations. Moreover, researchers have also tested the psychological effects of digital shinrin-yoku, which can provide virtual forest environments where almost similar therapeutic effects to an actual forest can be obtained [28]. Third, connecting with nature and experiencing it in a different light could impact how humans interact with the environment more sustainably. With forests and other ecosystems being harmed by climate change, the positive benefits can be two-fold. While immersing ourselves in nature, we may also consider doing something positive to give back to the environment at the same time, such as adopting a more sustainable lifestyle and advocating for more climate change policies that protect our earth.
Recommendations
As climate change continues, the impact on the mental health and wellbeing of the population will likely continue to increase. With the growing body of research on using shinrin-yoku to improve overall wellbeing, this case study offers the following recommendations.
First, considering the advantages of shinrin-yoku on overall mental health and wellbeing, and the increase in climate change concerns [29,30] and climate-related disasters worldwide, evaluating the effects of shinrin-yoku on climate-related mental health problems is a potential area for more research. Second, while there are effective prevention and treatment options for mental disorders, the majority of populations, particularly in low-and middle-income countries, lack access to mental health services [31]. Cost can also be a significant barrier to receiving treatment; hence, healthcare providers can prescribe shinrin-yoku as a cost-effective intervention, helping reduce inequalities in mental healthcare access. Third, as shinrin-yoku encourages people to spend more time in nature and around trees, policymakers need to ensure that necessary investments are available for maintaining an environment where trees are planted and protected, and more parks and green spaces in urban areas are developed. Lastly, the government should use policy tools to guide local governments and businesses to see the advantages of using the forest for health care, which is aligned with the growing trend around social and green prescribing in places such as Scotland [32]. This change in mindset does not only expand our therapeutic toolbox but could reduce the destruction of forest resources by local governments and promote the consideration of the positive effects of a circular economy [33].
This case study shows how the practice of shinrin-yoku in Japan can potentially become an effective intervention against the harmful effects of climate change on both the environment and mental health. While the majority of the research on shinrin-yoku has been conducted in Japan, East Asia, and Europe, future research could look more into the effects of shinrin-yoku in low- and middle-income countries as well as Indigenous communities who are more vulnerable to the effects of climate change. Moreover, while the effects of shinrin-yoku on general anxiety have been greatly studied, more research is needed on the effectiveness of shinrin-yoku prescribed as an intervention for those affected by climate change.
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Written by
Niaya Harper Igarashi